1. Field
The present description relates to thermal management of semiconductor devices and in particular to sensing temperature on a memory or I/O (Input/Output) interface chip and generating interrupts to a thermal management system.
2. Related Art
Semiconductor devices generate heat internally that, if left uncontrolled, can destroy the device. The heat generated by a device is related to its operating speed, its operating voltage and its level of activity. To dissipate extra heat, a device may be equipped with a large cooling surface, heat fins, fans or a more complex liquid cooling system. The cooling system allows the device to operate at some level of activity without overheating.
Semiconductor devices are normally designed to operate at a fixed speed and voltage based on a prediction of normal activity levels and cooling systems. As a result, when the device has less activity or is provided with better cooling, the device operates at a lower bandwidth than its cooling system would allow. In other words the device handles less data more slowly than it could. Even at expected activity and cooling levels, many devices run at a lower rated bandwidth in order to accommodate a sudden increase in activity.
In the event of an extended increase in activity or a failure of the cooling system, some semiconductor devices use some type of thermal management system that can protect the device from overheating before a crisis occurs. In a memory controller hub (MCH) or host controller, the thermal management system may analyze the level of I/O activity being processed or waiting to be processed and then reduce the rate of data processing if there is too much activity. This approach cannot compensate for a failed fan or overheated room.
An MCH may be used to interface one or more CPUs (central processing units) with memory and I/O (input/output) devices commonly used in desktop, notebook, workstation and server-based computer systems including web servers, transaction based servers, database management servers, file servers, and blade/network servers. These systems can experience situations that cause unforeseen surges in the chipset activity. Some such situations include a power virus caused by hacker activity or an unusually loaded system with very high utilization. The MCH and the rest of the chipset then are forced to supply a high request rate across the chipset interfaces causing high power demands and generating more heat. If the high request rate lasts for too long, then the chip may be permanently damaged by the heat that it generates.